JPS6034725Y2 - engine valve - Google Patents

Description

[Detailed explanation of the idea] This invention relates to the improvement of engine valves.

Engine valves provided in combustion chambers are now required to withstand high-temperature atmospheres and to be able to operate at higher speeds as engines are required to have higher output.

For this reason, it is desirable for engine valves to be as lightweight as possible and have a cooling effect.In the past, hollow cooling valves filled with sodium were the typical solution to meet these demands, but these valves were expensive and There were drawbacks such as the danger associated with handling sodium.

Therefore, the present invention is an economical and safe engine valve that is lightweight and has a cooling effect, eliminating the drawbacks of sodium cooling valves. The present invention proposes an engine valve having a structure in which the core is fixed within the valve head and a space is provided inside the valve shaft.

Further, since a space is provided inside the valve stem, deformation of the valve stem due to volumetric expansion of the core can be prevented.

Hereinafter, the present invention will be specifically explained with reference to the embodiments shown in FIGS. 1 and 2.

Here, the valve head 1 refers to the engine valve from the bulk part to the rounded neck part, and the valve stem 2 refers to the valve head 1.
The lower shaft part from the rounded root of the shaft, both of which are made of steel.

In the first embodiment shown in FIG. 1, a core 3 made of aluminum or magnesium is loaded into a round rod or pipe material with a hole drilled in the center in advance, and a space 4 is left inside the valve stem 2 facing the end of the core. In this way, a step is provided between the outer diameter of the core 3 and the hole diameter of the space 4, and a stopper 5 for fixing the core 3 is provided, which is upset-forged to form the valve head 1 and finished.

The manufacturing method of this embodiment is based on the patent No. 855368 (method for forming the head of a hollow engine valve) and the patent No. 857153 (method for forming the saw-shaped metal product with a hollow shaft), both of which were previously invented by the present inventors. If the technique shown is applied, there is no fear that the loaded core 3 will loosen, and the step between the outer diameter of the plug 5 or the core 3 and the hole diameter of the space 4 can be omitted.

(However, when applying the above-mentioned patent No. 855368, no technology regarding insert removal is required.

) Next, in the second embodiment shown in FIG. 2, contrary to the first embodiment, after forming the valve head 1, a hole is drilled in the center of the valve head 1 and the valve stem 2, and a hole is formed in the center of the valve head 1 and the valve stem 2. This is for loading the core 3.

In this embodiment, the core 3 is formed with a head-shaped portion, and the valve head 1 is formed with a recess that fits into the same head-shaped portion, so that both portions fit together and a space 4 is provided within the valve stem 2. and insert the core 3 into the valve head 1
The rear column 5 loaded in the valve stem 2 is placed over the three-head shaped portion of the core, and the core 3 is fixed within the valve head 1 by projection welding between the plug 5 and the valve head 1. ing.

In the second embodiment, a simple cylindrical shape is press-fitted into the core 3 without a head shape, or the plug 5 is omitted and the core 3 is
and the valve head 1 may be fixed by direct welding.

In the first and second embodiments described above, the wick 3 is fixed inside the valve head 1, which is the maximum operating temperature range of the valve, so that the wick 3 does not loosen during use. is valve head 1
However, it may also be fixed to the valve shaft 2.

Furthermore, in order to avoid deformation of the valve body due to volumetric expansion of the core 3, the space 4, which has a minimum volume limit, is better to be made small in order to lower the operating temperature of the valve. It is better to make the core 3 larger in order to reduce its weight, but for the former effect of lowering the valve operating temperature, the loading length of the core 3 should be made larger than the valve shaft 2 in contact with the valve guide.
Since there is no practical problem even if it is stopped at a position in the middle of , it is better to take this point into consideration and make the space 4 as large as possible in order to reduce the weight.

In particular, the core 3 may be formed into a hollow column shape in order to reduce the weight.

Note that when the core 3 is formed into a hollow columnar shape, the thermal expansion of the core 3 can be absorbed within the hollow space, so that the valve can be constructed without necessarily providing the space 4.

In addition to pure aluminum or pure magnesium, the core 3 may of course be made of an aluminum alloy or a magnesium alloy.

As mentioned above, the present invention uses an aluminum or magnesium core that has a light specific gravity and extremely high thermal conductivity, so it is approximately 15 to 20 degrees lighter than a normal solid automobile engine valve. An engine valve that can reduce the operating temperature by several tens of degrees Celsius or more is advantageous because it can be obtained safely and economically.

Further, according to the present invention, since there is a space inside the valve stem, the weight of the valve stem can be reduced, and at the same time, deformation of the valve stem due to volumetric expansion of the core can be effectively prevented.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are sectional views each showing a perspective view. 1... Valve head, 2... Valve shaft, 3...
・・Core (aluminum, magnesium), 4・・・・
·space.

Claims (1)

[Scope of utility model registration request] A core made of aluminum, aluminum alloy, agnesium or magnesium alloy is loaded inside a steel valve head and valve stem, and the core is fixed within the valve head, and a space is provided inside the valve stem. engine valve.